植被动态控制黑河流域典型生态系统能量分配——观测及数值模拟（英文）

Understanding the controls on seasonal variation of energy partitioning and separation between canopy and soil surface are important for qualifying the vegetation feedback to climate system.Using observed day-to-day variations of energy balance components including net radiation,sensible heat flux,latent heat flux ground heat flux,and meteorological variables combined with an energy-balanced two-source model,energy partitioning were investigated at six sites in Heihe River Basin from 2014 to 2016.Bowen ratio(β) among the six sites exhibited significant seasonal variations while showed smaller inter-annual fluctuations.All ecosystems exhibit a "U-shaped" pattern,characterized by smaller value of β in growing season,with a minimum value in July,and fluctuating day to day.During the growing season,average Bowen ratio was the highest for the alpine swamp meadow(0.60 ± 0.30),followed by the desert riparian forest Populus euphratica(0.47 ± 0.72),the alpine desert(0.46 ± 0.10),the Tamarix ramosissima desert riparian shrub ecosystem(0.33 ± 0.57),alpine meadow ecosystem(0.32 ± 0.17),and cropland ecosystem(0.27 ± 0.46).The agreement of Bowen ratio between simulated and observed values demonstrated that the two-source model is a promising tool for energy partitioning and separation between canopy and soil surface.The importance of biophysical control explains the convergence of seasonal and annual patterns of Bowen ratio for all ecosystems,and the changes in Bowen ratio showed divergence among varied ecosystems because of different physiological responses to energy flow pathways between canopy and soil surface.     

历史及未来气候变化下中国潜在植被NPP的脆弱性研究（英文）

Using the Integrated Biosphere Simulator, a dynamic vegetation model, this study initially simulated the net primary productivity(NPP) dynamics of China's potential vegetation in the past 55 years(1961–2015) and in the future 35 years(2016–2050). Then, taking the NPP of the potential vegetation in average climate conditions during 1986–2005 as the basis for evaluation, this study examined whether the potential vegetation adapts to climate change or not. Meanwhile, the degree of inadaptability was evaluated. Finally, the NPP vulnerability of the potential vegetation was evaluated by synthesizing the frequency and degrees of inadaptability to climate change. In the past 55 years, the NPP of desert ecosystems in the south of the Tianshan Mountains and grassland ecosystems in the north of China and in western Tibetan Plateau was prone to the effect of climate change. The NPP of most forest ecosystems was not prone to the influence of climate change. The low NPP vulnerability to climate change of the evergreen broad-leaved and coniferous forests was observed. Furthermore, the NPP of the desert ecosystems in the north of the Tianshan Mountains and grassland ecosystems in the central and eastern Tibetan Plateau also had low vulnerability to climate change. In the next 35 years, the NPP vulnerability to climate change would reduce the forest–steppe in the Songliao Plain, the deciduous broad-leaved forests in the warm temperate zone, and the alpine steppe in the central and western Tibetan Plateau. The NPP vulnerability would significantly increase of the temperate desert in the Junggar Basin and the alpine desert in the Kunlun Mountains. The NPP vulnerability of the subtropical evergreen broad-leaved forests would also increase. The area of the regions with increased vulnerability would account for 27.5% of China.     

Water sources of plants and groundwater in typical ecosystems in the lower reaches of the Heihe River Basin

Stable oxygen and hydrogen isotopic compositions （δ18O and δD） of soil water and shallow groundwater of a riparian forest, an artificial shrub forest, and Gobi of the lower reaches of the Heihe River Basin are used to study the recharge water sources of those ecosystems. IsoSource software is used to determine the δ180 values for root water of Populous euphratica and Tamarix ramosissima in the riparian forest ecosystem, Haloxylon ammodendron in the artificial shrub forest, and Reaumuria soongorica in the Gobi, as well as for local soil water and groundwater, and precipitation in the upper reaches of the Heihe River Basin. Our results showed that soil water and shallow groundwater of the riparian forest and the artificial shrub forest were recharged by river water which originated from precipitation in the upper reaches, and strong evaporation occurred in the artificial shrub forest. Soil water of the Gobi was not affected by Heihe River water due to this area being far away from the river channel. The main water sources of Populous euphratica were from 40-60-cm soil water and groundwater, and of Tamarix ramosissima were from 40-80-cm soil water in the riparian forest ecosystem. In the artificial forest, Haloxylon ammodendron used 200-cm saturated-layer soil water and shallow groundwater. The Reaumuria soongorica mainly used soil water from the 175-200-cm depth in the Gobi. Therefore, soil water and groundwater are the main water sources which maintain survival and growth of the plants in the extremely arid regions of the lower reaches of the Heihe River Basin.     

Influence of canopy and topographic position on soil moisture response to rainfall in a hilly catchment of Three Gorges Reservoir Area,China

Rainfall provides essential water resource for vegetation growth and acts as driving force for hydrologic process, bedrock weathering and nutrient cycle in the steep hilly catchment. But the effects of rainfall features, vegetation types, topography, and also their interactions on soil water movement and soil moisture dynamics are inadequately quantified. During the coupled wet and dry periods of the year 2018 to 2019, time-series soil moisture was monitored with 5-min interval resolution in a hilly catchment of the Three Gorges Reservoir Area in China. Three hillslopes covered with evergreen forest(EG), secondary deciduous forest mixed with shrubs(SDFS) and deforested pasture(DP) were selected, and two monitoring sites with five detected depths were established at upslope and downslope position, respectively. Several parameters expressing soil moisture response to rainfall event were evaluated, including wetting depth, cumulative rainfall amount and lag time before initial response, maximum increase of soil water storage, and transform ratio of rainwater to soil water. The results indicated that rainfall amount is the dominant rainfall variable controlling soil moisture response to rainfall event. No soil moisture response occurred when rainfall amounts was 8 mm, and all the deepest monitoring sensors detected soil moisture increase when total rainfall amounts was 30 mm. In the wet period, the cumulative rainfall amount to trigger surface soil moisture response in EG-up site was significantly higher than in other five sites. However, no significant difference in cumulative rainfall amount to trigger soil moisture response was observed among all study sites in dry period. Vegetation canopy interception reduced the transform ratio of rainwater to soil water, with a higher reduction in vegetation growth period than in other period. Also, interception of vegetation canopy resulted in a largeraccumulated rainfall amount and a longer lag time for initiating soil moisture response to rainfall. Generally, average cumulative rainfall amount for initiating soil moisture response during dry period of all sites(3.5–5.6 mm) were less than during wet period(5.7–19.7 mm). Forests captured more infiltration water compared with deforested pasture, showing the larger increments of both soil water storage for the whole soil profile and volumetric soil water content at 10 cm depth on two forest slopes. Topography dominated soil subsurface flow, proven by the evidences that less rainfall amount and less time was needed to trigger soil moisture response and also larger accumulated soil water storage increment in downslope site than in corresponding upslope site during heavy rainfall events.     

青藏高原植被覆盖变化与降水关系

The temporal and spatial changes of NDVI on the Tibetan Plateau, as well as the relationship between NDVI and precipitation, were discussed in this paper, by using 8-km resolution multi-temporal NOAA AVHRR-NDVI data from 1982 to 1999. Monthly maximum NDVI and monthly rainfall were used to analyze the seasonal changes, and annual maximum NDVI, annual effective precipitation and growing season precipitation (from April to August) were used to discuss the interannual changes. The dynamic change of NDVI and the corre- lation coefficients between NDVI and rainfall were computed for each pixel. The results are as follows: (1) The NDVI reached the peak in growing season (from July to September) on the Tibetan Plateau. In the northern and western parts of the plateau, the growing season was very short (about two or three months); but in the southern, vegetation grew almost all the year round. The correlation of monthly maximum NDVI and monthly rainfall varied in different areas. It was weak in the western, northern and southern parts, but strong in the central and eastern parts. (2) The spatial distribution of NDVI interannual dynamic change was different too. The increase areas were mainly distributed in southern Tibet montane shrub-steppe zone, western part of western Sichuan-eastern Tibet montane coniferous forest zone, western part of northern slopes of Kunlun montane desert zone and southeastern part of southern slopes of Himalaya montane evergreen broad-leaved forest zone; the decrease areas were mainly distributed in the Qaidam montane desert zone, the western and northern parts of eastern Qinghai-Qilian montane steppe zone, southern Qinghai high cold meadow steppe zone and Ngari montane desert-steppe and desert zone. The spatial distribution of correlation coeffi- cient between annual effective rainfall and annual maximum NDVI was similar to the growing season rainfall and annual maximum NDVI, and there was good relationship between NDVI and rainfall in the meadow and grassland with medium vegetation cover, and the effect of rainfall on vegetation was small in the forest and desert area.     

青藏高原高寒草地地上生物量对气候变化的响应（英文）

Aboveground biomass in grasslands of the Qinghai-Tibet Plateau has displayed an overall increasing trend during 2003–2016, which is profoundly influenced by climate change. However, the responses of different biomes show large discrepancies, in both size and magnitude. By applying partial least squares regression, we calculated the correlation between peak aboveground biomass and mean monthly temperature and monthly total precipitation in the preceding 12 months for three different grassland types(alpine steppe, alpine meadow, and temperate steppe) on the central and eastern Qinghai-Tibet Plateau. The results showed that mean temperature in most preceding months was positively correlated with peak aboveground biomass of alpine meadow and alpine steppe, while mean temperature in the preceding October and February to June was significantly negatively correlated with peak aboveground biomass of temperate steppe. Precipitation in all months had a promoting effect on biomass of alpine meadow, but its correlations with biomass of alpine steppe and temperate steppe were inconsistent. It is worth noting that, in a warmer, wetter climate, peak aboveground biomass of alpine meadow would increase more than that of alpine steppe, while that of temperate steppe would decrease significantly, providing support for the hypothesis of conservative growth strategies by vegetation in stressed ecosystems.     

Pollen-based reconstructions of Holocene vegetation and climatic change of Tibetan Plateau

A synthesis of Holocene pollen records from the Tibetan Plateau shows the history of vegetation and climatic changes during the Holocene. Palynological evidences from 24 cores/sections have been compiled and show that the vegetation shifted from subalpine/alpine conifer forest to subalpine/alpine evergreen sclerophyllous forest in the southeastern part of the plateau; from alpine steppe to alpine desert in the central, western and northern part; and from alpine meadow to alpine steppe in the eastern and southern plateau regions during the Holocene. These records show that increases in precipitation began about 9 ka from the southeast, and a wide ranging level of increased humidity developed over the entire of the plateau around 8-7 ka, followed by aridity from 6 ka and a continuous drying over the plateau after 4-3 ka. The changes in Holocene climates of the plateau can be interpreted qualitatively as a response to orbital forcing and its secondary effects on the Indian Monsoon which expanded northwards     

How changes of groundwater level affect the desert riparian forest ecosystem in the Ejina Oasis,Northwest China

Groundwater is a key factor controlling the growth of vegetation in desert riparian systems. It is important to recognise how groundwater changes affect the riparian forest ecosystem. This information will not only help us to understand the ecological and hydrological process of the riparian forest but also provide support for ecological recovery of riparian forests and water-resources management of arid inland river basins. This study aims to estimate the suitability of the Water Vegetation Energy and Solute Modelling(WAVES) model to simulate the Ejina Desert riparian forest ecosystem changes,China, to assess effects of groundwater-depth change on the canopy leaf area index(LAI) and water budgets, and to ascertain the suitable groundwater depth for preserving the stability and structure of desert riparian forest. Results demonstrated that the WAVES model can simulate changes to ecological and hydrological processes. The annual mean water consumption of a Tamarix chinensis riparian forest was less than that of a Populus euphratica riparian forest, and the canopy LAI of the desert riparian forest should increase as groundwater depth decreases. Groundwater changes could significantly influence water budgets for T. chinensis and P. euphratica riparian forests and show the positive and negative effects on vegetation growth and water budgets of riparian forests. Maintaining the annual mean groundwater depth at around 1.7-2.7 m is critical for healthy riparian forest growth. This study highlights the importance of considering groundwater-change impacts on desert riparian vegetation and water-balance applications in ecological restoration and efficient water-resource management in the Heihe River Basin.     

Land use effects on soil organic carbon, nitrogen and salinity in saline-alkaline wetland

Land-use and soil management affects soil organic carbon （SOC） pools, nitrogen, salinity and the depth distribution. The objective of this study was to estimate land-use effects on the distribution of SOC, labile fractions C, nitrogen （N） and salinity in saline-alkaline wetlands in the middle reaches of the Heihe River Basin. Three land-use types were selected： intact saline-alkaline meadow wetland, artificial shrubbery （planting Tamarix） and farmland （cultivated for 18 years） of soils previously under meadow wetland. SOC, easily oxidized carbon, microbial biomass carbon, total N, NO3--N and salinity concentrations were measured. The results show that SOC and labile fraction carbon contents decreased significantly with increasing soil depth in the three land-use wetlands. The labile fraction carbon contents in the topsoil （0-20cm） in cultivated soils were significantly higher than that in intact meadow wetland and artificial shrubbery soil. The aboveground biomass and soil permeability were the primary influencing factors on the contents of SOC and the labile carbon in the intact meadow wetland and artificial shrubbery soil, however, the farming practice was a factor in cultivated soil. Agricultural measures can effectively reduce the salinity contents; however, it caused a significant increase of NO 3--N concentrations which posed a threat to groundwater quality in the study area.     

Changes in plant species composition and diversity of alpine Kobresia (Kobresia pygmaea) steppe meadow at different stages of desertification in the North Tibetan plateau

The impacts of desertification on the vegetation composition, structure, and species diversity of alpine Kobresia steppe meadow were evaluated in an area of severe desertification in Anduo County, Tibet Autonomous Region, northern China. We investigated and analyzed the floristic features of communities at four different stages of desertification (slight desertification [SLD], moderate desertification [MD], severe desertification [SD], and very severe desertification [VSD]). The composition and structure of the alpine Kobresia steppe meadow at the SLD site differed significantly from that at the MD, SD, and VSD sites. Species that were more drought resistant and inedible by livestock were the dominant species at the SD site. No plants were found in the shifting dunes of the VSD site. Species diversity also decreased with increasing desertification. The SLD site had the largest mean number of species and individuals and the largest richness index; the MD grassland had the largest Shannon-Wiener index and evenness index, but the smallest Simpson’s index. The vegetation cover declined from 91.8% to 34.8% as desertification increased from SLD to SD, and reached 0% in VSD areas with shifting dunes.     

新疆伊犁河谷不同植被带下土壤有机碳分布(英文)

We analyzed and estimated the distribution and reserves of soil organic carbon under nine different vegetation conditions including alpine meadow,meadow steppe,typical steppe,desert steppe,and temperate coniferous forest and so on,in the Ili River valley,Xinjiang according to data from field investigations and laboratory analyses in 2008 and 2009.The study results show that the soil organic carbon content in the Ili River valley varies with the type of vegetation.In the 0-50 cm soil horizon,the soil organic carbon content is the highest under the vegetation types of alpine meadow and meadow steppe,slightly lower under temperate coniferous forest and typical steppe,and the lowest under the intrazonal vegetation and desert vegetation types.The soil organic carbon content shows basically a tendency to decrease as soil depth increases under various vegetation types except in the case of the intrazonal vegetation.Similarly,the soil organic carbon density is the highest and varies little under the vegetation types of alpine meadow,meadow steppe and temperate coniferous forest,and is the lowest under the desert vegetation type.Both the soil organic carbon content and density in the topsoil of meadows in the Ili River valley are high,so protecting meadows in the Ili River valley,and especially their topsoil,should be a priority so that the potential of change in soil organic carbon in the shallow soil horizon is reduced,and this means maintenance of the stability of the soil carbon pool.     

伊犁河谷不同植被带下土壤有机碳分布

结合2008年和2009年野外实地调查与室内分析的资料,运用方差分析等方法对伊犁河谷高山草甸、草甸草原、典型草原、荒漠草原、温性针叶林等9种不同植被条件下的土壤有机碳含量分布及其储量进行了分析估算.研究结果表明:伊犁河谷土壤有机碳含量因植被类型变化而不同.在0～50 cm土层范围,高山草甸、草甸草原土壤有机碳含量较高,其次是温性针叶林和典型草原,含量最低的是隐域植被和荒漠植被土壤.除隐域植被外,各植被类型下土壤有机碳含最基本呈随着土层深度增加而降低的,变化趋势.有机碳密度同样是高山草甸、草甸草原和温性针叶林土壤有机碳密度较高且比较相近,荒漠植被下土壤有机碳密度最低.伊犁河谷草地表层土壤有机碳含量高、密度大,因此应重视对伊犁河谷草地的保护,尤其要保护草地表层土壤以降低浅层土壤有机碳发生变化的可能性,维护土壤碳库的稳定性.     

Distribution of soil organic carbon under different vegetation zones in the Ili River Valley,Xinjiang

We analyzed and estimated the distribution and reserves of soil organic carbon under nine different vegetation conditions including alpine meadow, meadow steppe, typical steppe, desert steppe, and temperate coniferous forest and so on, in the Ili River valley, Xinjiang according to data from field investigations and laboratory analyses in 2008 and 2009. The study results show that the soil organic carbon content in the Ili River valley varies with the type of vegetation. In the 0–50 cm soil horizon, the soil organic carbon content is the highest under the vegetation types of alpine meadow and meadow steppe, slightly lower under temperate coniferous forest and typical steppe, and the lowest under the intrazonal vegetation and desert vegetation types. The soil organic carbon content shows basically a tendency to decrease as soil depth increases under various vegetation types except in the case of the intrazonal vegetation. Similarly, the soil organic carbon density is the highest and varies little under the vegetation types of alpine meadow, meadow steppe and temperate coniferous forest, and is the lowest under the desert vegetation type. Both the soil organic carbon content and density in the topsoil of meadows in the Ili River valley are high, so protecting meadows in the Ili River valley, and especially their topsoil, should be a priority so that the potential of change in soil organic carbon in the shallow soil horizon is reduced, and this means maintenance of the stability of the soil carbon pool.     

高寒河谷灌丛冠层降雨再分配特征及影响因素

通过植被冠层的降雨被分割成冠层截留、穿透雨和树干茎流3个部分,这个过程（冠层降雨再分配）是高寒河谷灌丛生态演变的关键驱动因子之一,对于认识高寒河谷灌丛的水文循环过程及水分收支规律也具有重要意义。选取青海湖流域最重要的河谷灌丛--具鳞水柏枝作为研究对象,通过野外定点观测,深入分析了冠层降雨再分配特征及影响因素\.结果显示:①穿透雨量、树干茎流量、冠层截留量占同期降雨量的比例平均为48.40%、4.04%和47.56%,并在不同降雨量等级之间存在显著差异;②冠层降雨再分配各组成要素（穿透雨、树干茎流、冠层截留）与降雨特征参数存在高度相关性,伴随降雨量和降雨历时的增加,穿透雨量、树干茎流量、冠层截留量占同期降雨量的比例均逐渐趋于稳定,极限稳定值分别介于60.45%～61.07%、6.45%～7.42%、33.11%～34.17%;③产生穿透雨和树干茎流的临界降雨量分别为1.10 mm和1.87 mm,表明2 mm以下的降雨对土壤水分的补给基本没有贡献。因此,高寒河谷灌丛冠层降雨再分配与其他林木类型存在明显差异,需要深入研究其内在机制及水分利用规律。     

青藏高原植被垂直带与气候因子的空间关系

集成了青藏高原气候区149个山地植被垂直带数据,利用国家基本气象台站自建站以来到2001年的地面观测日气象数据,计算了地面的温暖(WI)、寒冷(CI)、湿润(MI)、吉良龙夫(Kira)干湿指数、干燥度(Idm)等水热指数,运用GIS的空间分析模块,模拟了青藏高原水热条件的空间分布形势,探讨山地植被垂直带谱分布规律与制约因子的定量指标.结果表明:在高原的东北部、西北边缘,以荒漠、荒漠草原、山地森林、山地草原、灌丛、草甸为组合的半干旱、干旱结构向高原腹地以高寒草原、高山草甸、荒漠带组合的高寒干旱带谱结构的变化;东南、南部边缘,以温暖湿润为特征的以森林带为优势带谱组合结构逐渐向寒冷的高原中心变化;高原的地势效应,致使的水热形势旱现从中央向边缘变化的趋势是致使青藏高原植被垂直带谱分布的重要原因.     

NPP vulnerability of the potential vegetation of China to climate change in the past and future

Using the Integrated Biosphere Simulator, a dynamic vegetation model, this study initially simulated the net primary productivity (NPP) dynamics of China’s potential vegetation in the past 55 years (1961–2015) and in the future 35 years (2016–2050). Then, taking the NPP of the potential vegetation in average climate conditions during 1986–2005 as the basis for evaluation, this study examined whether the potential vegetation adapts to climate change or not. Meanwhile, the degree of inadaptability was evaluated. Finally, the NPP vulnerability of the potential vegetation was evaluated by synthesizing the frequency and degrees of inadaptability to climate change. In the past 55 years, the NPP of desert ecosystems in the south of the Tianshan Mountains and grassland ecosystems in the north of China and in western Tibetan Plateau was prone to the effect of climate change. The NPP of most forest ecosystems was not prone to the influence of climate change. The low NPP vulnerability to climate change of the evergreen broad-leaved and coniferous forests was observed. Furthermore, the NPP of the desert ecosystems in the north of the Tianshan Mountains and grassland ecosystems in the central and eastern Tibetan Plateau also had low vulnerability to climate change. In the next 35 years, the NPP vulnerability to climate change would reduce the forest–steppe in the Songliao Plain, the deciduous broad-leaved forests in the warm temperate zone, and the alpine steppe in the central and western Tibetan Plateau. The NPP vulnerability would significantly increase of the temperate desert in the Junggar Basin and the alpine desert in the Kunlun Mountains. The NPP vulnerability of the subtropical evergreen broad-leaved forests would also increase. The area of the regions with increased vulnerability would account for 27.5% of China.     

应用地统计学方法定量评价森林截留的地理变化规律

收集大量森林生态系统类型林冠截留功能研究资料,应用地统计学方法模拟了我国主要森林生态系统类型林冠截留的地理变化规律。结果表明:我国主要森林生态系统类型林冠截留与环境因素经度和纬度之间存在一定的地理变化规律,地统计学方法模拟的回归优度达88.15%,明显优于前人提出的三因素多元地理空间模型的模拟效果(回归优度为56.42%),能更真实反映我国主要森林生态系统类型林冠截留的地理变化规律,从而为我国主要森林生态系统林冠截留时空分布的模拟与分析提供可靠方法。这些主要森林生态系统包括:寒温带、温带山地落叶针叶林;寒温带、温带山地常绿针叶林;亚热带、热带东部山地常绿针叶林;亚热带、热带西部山地常绿针叶林;亚热带西部高山常绿针叶林;温带山地落叶与常绿针叶林;温带、亚热带山地落叶阔叶林;亚热带山地常绿阔叶林;亚热带山地常绿落叶阔叶混交林;亚热带竹林;南亚热带山地季风常绿阔叶林;热带半落叶季风雨林;热带山地雨林。     

Protecting the national parks and the world heritage sites in China: challenge and strategy

To protect the richness, diversity and uniqueness of China's ecosystems and landscapes, more than 150 national parks (named "National scenic and historic interest areas" in China), 85 national geoparks and 230 national nature reserves have been delimited nationwide. In addition, a total of 30 world heritage sites (4 mixed, 4 natural, 22 cultural), 24 biosphere reserves and 8 world geoparks have been ratified for China in a short time by the UNESCO. Unfortunately, most of these national and…     

黑河流域荒漠区土壤水分对降水脉动响应

 利用气象站资料,对黑河流域荒漠区降水特征及其土壤水分对降水脉动响应进行了系统研究。结果表明,荒漠区降水属于降水脉动事件,降水前后土壤水分特征存在显著差异,且随土层增加差异逐渐变小。土壤水分在降水量、土壤深度和降水前后的差异极显著,交互效应也极显著(P<0.0001),表明荒漠区土壤水分对降水脉动具有显著的响应现象。土壤水分的降水脉动响应表现为降水后土壤含水量激增,在蒸散作用下缓慢减小。降水前后土壤含水量的时间序列变异规律均能较好地拟合成变异函数的理论模型。降水前后土壤含水量随机变异均小于结构性变异,反映出荒漠区土壤水分在时间尺度上具有较强的自相关性格局。降水使土壤水分空间结构差异呈现下降趋势,在时间序列上异质性降低。     

The relationship between NDVI and precipitation on the Tibetan Plateau

The temporal and spatial changes of NDVI on the Tibetan Plateau, as well as the relationship between NDVI and precipitation, were discussed in this paper, by using 8-km resolution multi-temporal NOAA AVHRR-NDVI data from 1982 to 1999. Monthly maximum NDVI and monthly rainfall were used to analyze the seasonal changes, and annual maximum NDVI, annual effective precipitation and growing season precipitation (from April to August) were used to discuss the interannual changes. The dynamic change of NDVI and the corre-lation coefficients between NDVI and rainfall were computed for each pixel. The results are as follows: (1) The NDVI reached the peak in growing season (from July to September) on the Tibetan Plateau. In the northern and western parts of the plateau, the growing season was very short (about two or three months); but in the southern, vegetation grew almost all the year round. The correlation of monthly maximum NDVI and monthly rainfall varied in different areas. It was weak in the western, northern and southern parts, but strong in the central and eastern parts. (2) The spatial distribution of NDVI interannual dynamic change was different too. The increase areas were mainly distributed in southern Tibet montane shrub-steppe zone, western part of western Sichuan-eastern Tibet montane coniferous forest zone, western part of northern slopes of Kunlun montane desert zone and southeastern part of southern slopes of Himalaya montane evergreen broad-leaved forest zone; the decrease areas were mainly distributed in the Qaidam montane desert zone, the western and northern parts of eastern Qinghai-Qilian montane steppe zone, southern Qinghai high cold meadow steppe zone and Ngari montane desert-steppe and desert zone. The spatial distribution of correlation coeffi-cient between annual effective rainfall and annual maximum NDVI was similar to the growing season rainfall and annual maximum NDVI, and there was good relationship between NDVI and rainfall in the meadow and grassland with medium vegetation cover, and the effect of rainfall on vegetation was small in the forest and desert area.